Navy signal flags and pennants include six that pertain directly to maneuvering:

Name

Pennant

Name

Pennant

CORPEN

STATION

TURN

SCREEN

FORMATION

SPEED

Signals using these basic maneuvering flags are called maneuvering signals.

Additional flags used in maneuvering are:

No.

Flag

Pennant

No.

Flag

Pennant

Name

Pennant

1

6

ANS

2

7

PORT

3

8

STBD

4

9

5

0

In Different PositionsNumbers MeanDifferent Things

A complete maneuvering signal contains one or more maneuvering flags and pennants, followed or preceded by numeral flags.

Three numeral flags indicate a true course or a true bearing, depending upon the maneuvering flag or pennant with which they are displayed.

When fewer than three flags are hoisted, they indicate a relative change of course or bearing in 10-degree units.

The ANSWER pennant indicates half units, 5-degree increments, a fraction (1/2), or a decimal point. If the OTC desires to send a signal for a change of speed to 16.5 knots, for example, the Signalmen would hoist SPEED ONE SIX ANS. For a speed of 12.7 knots, however, they would hoist SPEED ONE TWO ANS SEVEN.

CORPEN

The CORPEN pennant is spoken, written, and transmitted CORPEN. It is used to change the course of ships in succession (known as column movement or wheeling) or, with a modifier, to indicate a course of a ship formation. When CORPEN is used to alter course by wheeling in a relative direction from dead ahead, it precedes the PORT flag or STARBOARD pennant and one or two numeral flags, which indicate the number of tens of degrees; three numeral flags would indicate the course on which to steady.

Examples:

CORPENSTBD9

Alter courseby wheeling tostarboard 90 degrees

CORPENPORT090

Alter course by wheeling to port to course 090

CORPENPORT4ANS

Alter course by wheeling to port45 degrees

TURN

The TURN pennant, spoken, written, and transmitted TURN, may be used in any formation. It requires that all addressees put over their rudders simultaneously when the execute signal is given. Interpretation of these signals is always a turn together to starboard or to port.
The direction and specified amount of the turn must be indicated. TURN precedes the PORT flag or STARBOARD pennant and one or two numeral flags that indicate the amount of degrees of the turn in tens of degrees relative to the present course; three numeral flags indicate the course on which to steady.

Examples:

TURNSTBD9

Ships turn together to starboard 90 degrees

TURNPORT270

Ships turn together to port to course 270 degrees

TURNSTBD1ANS

Ships turn together to starboard 15 degrees

FORMATION

The FORMATION pennant, spoken FORMATION but written and transmitted FORM, is used to assemble ships in a formation or to change a formation. The most common use of a FORM signal is to order a group of ships to arrange or rearrange themselves on an indicated line of bearing from the guide. When the desired direction is true, the usual three numeral flags are hoisted. When indicated bearing is relative, inclusion of the PORT flag or STARBOARD pennant determines whether the line of bearing is to the right or left of the guide.

Examples:

FORM225

Ships are to form on true bearing of 225° from guide.

FORMPORT9

Ships are to form on relative bearing indicated in tens of degrees from guide

(In this instance, 090° means relative to port side of the guide).

Relative bearings are always 000° to 359° clockwise around the ship. For purposes of forming up, however, these bearings run only to 180°—bow to stern—and may be on either side of the ship. A good reason for that is there are a number of standard form signals consisting simply of FORM and a number. For instance, FORM 9 without a direction pennant means “Form divisions in line abreast to starboard, division guides bearing astern,” a signal entirely different from FORM PORT 9.

Although execution of a FORM signal may require a change of course to carry out the maneuver, the final course always is the same as the original course. The only element that changes is the maneuvering ship's position relative to the guide.

STATION

The STATION pennant—spoken, written, and transmitted STATION—is used mainly to assign position or station to a ship or unit that is joining another ship or unit, or to move a ship or unit from one station to another. When accompanied by a distance or interval signal, the pennant indicates the distance a ship or unit is to be stationed from the guide or from the ship indicated in the signal.
When accompanying a ship's call sign, STATION alone directs that ship to take its proper and assigned station.

SCREEN

The SCREEN pennant is spoken, written, and transmitted SCREEN. It is used in signaling various screening situations.

SUBSTITUTES

FIRST SUB

SECOND SUB

THIRD SUB

FOURTH SUB

Whenever possible, substitutes are used to prevent alphabet flags, numeral flags, or numeral pennants from appearing more than once in the same hoist. As their names imply, they are substitutes for other flags or pennants used in the hoist.

When more than one halyard is used to hoist a signal, each hoist is considered separately as regards substitutes. When a tackline separates hoist components, it is disregarded in the substitute count.
Substitutes also are used as “absence indicators” when a ship is not under way.